A person facing a legal hearing often has a friend who promises to testify for him. Unfortunately, when the day arrives the friend can’t be present at court but he says that he will write a letter for the judge to see.
Lawyers cringe when a client asks why the judge won’t accept the letter. The court has good reason; it is against the law. It is a witness that the opposing lawyer cannot cross examine.
Think of it this way. Your are being tried in court and the other side gets to put on a letter that says you are guilty. You can’t cross examine the missing witness as to why he believes you’re guilty. You can’t ask the paper that the missing witness submitted if he even saw the crime. You can’t ask the missing witness anything. A client would say, “It’s not fair!”
A letter from a person who could not attend court isn’t fair to anyone. If you have a person who could help your case, tell your attorney. He will get the witness subpoenaed. The witness is protected from being fired from his job, excused from school, etc. for attending court.
Then he really will be a witness.